Stereoscopic displays based on the use of lenticular lens arrays typically employ very narrow pitch lenslets, generally on the order of 0.02 inches in width. In this type of display, each eye of the observer sees one constant color across the width of one lenslet.
Behind each lenslet, a printed or computer-modulated display provides a set of closely spaced colored point sources, each separated from the one next to it by a small horizontal offset. The lenslet converts the relative horizontal position of each colored point source into a corresponding angular direction.
A stereoscopic impression of depth is imparted by the disparity between the color seen by the left eye and the color seen by the right eye, as both eyes regard the same lenslet from different angles.
When a computer display is used to provide the colored point sources, there is a trade-off between spatial resolution and angular resolution of the resulting 3D image: If each lenslet is required to provide a different color into N distinct angular directions, then the number of image pixels available to the eye of any given observer is correspondingly reduced by a factor of N.
A special case of lenslet based stereoscopic display is an autostereoscopic display that employs only two source pixels behind each lenslet. In this type of display the observer must maintain a relatively fixed head position, and must remain at a specific distance away from the display surface. An advantage of this type of autostereoscopic display is that the loss of resolution for this single properly positioned observer is only a factor of two (half of the source pixels are routed to the observer's left eye, and the other half are routed to the observer's right eye).
Given the advent of progressively more affordable methods to actively track the position of an observer's eyes, through the use of a video camera and computer software, it is now possible to radically rethink the use of lenticular lenslet arrays for autostereoscopic displays.